The present invention relates to a radial compressor and in particular to a scotch yoke radial compressor adapted for use in an automotive air-conditioner.
Automotive air conditioning systems require small, lightweight compressors which can be conveniently mounted to the engine and driven by the same belt system that drives the fan, alternator and power steering pump. One compressor which has been found to meet these requirements is a radial compressor wherein a plurality of pistons are reciprocated within cylinders radially disposed about the crankshaft.
One problem with this type of compressor, however, is the difficulty of assembling the pistons to the crankshaft and crankcase. One prior art approach is to insert the pistons through the cylinders and then press fit them to the yoke assembly. A more satisfactory technique is disclosed in U.S. Pat. No. 3,910,164, which discloses a radial compressor wherein the crankcase is split, with each of the two halves including a plurality of semicylindrical cross recesses. The piston assembly is placed in one of the crankcase halves and then the other half is secured thereto. A relatively wide annular flexible Teflon seal compensates for small tolerance mismatch between the piston bore forming registering cross recesses. An obvious difficulty with this design is providing a good seal between the crankcase halves, which is necessary to prevent leakage. This problem is especially troublesome in the case of aluminum crankcases, which have surfaces that are porous in nature.